The major aim of the project is the study of the structure and mechanism of action of metalloenzymes. Major objects of study are carbonic anhydrase, alkaline phosphatase, T7 RNA polymerase and the copper proteins, superoxide dismutase, laccase, and tyrosinase. The function of metal ions in transcription, particularly the role of Zn(II) in RNA polymerase is under investigation. Physicochemical methods applied to these systems include optical spectroscopy (absorption, circular dichroism, and magneto circular dichroism), electron spin resonance (of transition metals at active sites and spin-labeled substrates and inhibitors), as well as rapid flow and steady-state kinetic studies and chemical modification of the proteins. An X-ray crystallographic study of alkaline phosphatase of E. coli is also being carried out.